Oracle is trying to make sure its billion-dollar copyright dispute with Google over the Android OS doesn’t make it to the U.S. Supreme Court.

The companies have been battling for years over whether Google infringed Oracle’s copyright when it lifted programming interfaces from Java for use in its Android mobile OS.

There’s a lot of money at stake, with Oracle seeking at least US$1 billion for the alleged infringement. Some programmers are also watching the case, believing the outcome will affect their freedom to use other software APIs (application programming interfaces).

“To hold unprotectable the thousands of lines of code Google copied would strip all code of copyright protection,” Oracle told the Supreme Court Monday, urging it to let the appeals court decision stand.

Google has argued that it had no choice but to copy parts of Java when it developed Android, because Java was already popular and programmers needed the familiar APIs to write Java programs. Such “functional” code isn’t even eligible for protection under U.S. copyright law, Google said.

That’s the central question Google wants the Supreme Court to decide. But Oracle says the law is already clear.

“There is no dispute that Google was free to write its own code to perform the same functions as Oracles,” it’s lawyers wrote. “Instead, it plagiarized.”

The Supreme Court doesn’t agree to hear all cases, only those where it thinks it can settle an important point of law. If it declines to hear the case, it may be sent back to the district court for another trial. If it accepts the case, programmers will be watching to see the implications for copyright and APIs.

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